The present invention pertains to an electrolysis method and an electrolyzer wherein it is possible to create a sterilizing and cleansing water by electrolyzing a solution containing a halogen ion in order to sterilize and wash medical equipment, dishes, food, hands, etc.
In the prior art, a platinized titanium electrode plate has been used as an electrode in order to create an electrolyte having a sterilizing and cleansing function, and in particular, it was used as an anode in a strongly acidic and strong acidifying environment. However, it has a problem in that it cannot withstand usage over a long period of time. From the point of view of having good anti-corrosivity, a nickel ferrite electrode (Japanese Laid-Open Patent Publication No. S53-9273/1978) has been used as a replacement. However, when the electric current is increased in order to improve the effect of the sterilization and cleansing, the terminal parts become hot, and consequently, the ferrite breaks due to thermal distortion, or the plastic case of the electrolytic reaction device became distorted due to thermal expansion.
With respect to above-mentioned ferrite, the present inventors have filed the patent applications which are published as Japanese Laid-Open Patent Publication Nos. 11-188364 and 11-309458. In the inventions disclosed in these publications, the present inventors achieved long lasting performance of electrodes that is three to five times longer, under the same conditions, than a conventional hand sterilizing or cleansing device with a platinum plated titanium electrode.
However, there was a problem such that when electric current applied to the electrode is further increased in order to obtain a greater sterilizing or cleansing effect, the temperature of a terminal part of the electrode increases. The increased temperature would cause deformation of a plastic case of the electrolyzer and leakage of electrolyte. In addition, in order for an electrolyzer to be simply installed in a home or hospital room, a small sized device that creates a sterilizing or cleansing solution was required. Downsizing of the electrolyzer further caused the risk of temperature raise of the terminal part.
In order to solve these problems, the object of the present invention is to provide an electrolyzer that is compact and long lasting capability and has superior electrolysis performance. Another object of this invention is to prevent the heat increase of a terminal part of an electrode when electric current applied is increased, even though the electrolyzer is in the small size. For these purposes, a nickel ferrite anode of an electrolyzer was improved so that thermal expansion and the deformation of the plastic case due to the overheating of the electrode were avoided along with the associated problem of liquid leakage. In addition, the entire shape of the electrolyzer was made into cylindrical so that it can form a durable structure.
Multiple anodes and cathodes are alternated in a concentric manner, with some space between the electrodes in a layer, so that the solution containing halogen ions between the electrodes is electrolyzed and sterilizing and cleansing water is created. For the anode, a nickel ferrite electrode was used because it is less expensive than platinum and it has a superior anti-corrosive property that is similar to platinum.
At the anode, halogen ions are precipitated as chlorine or bromine, and immediately a reaction is carried out with water. Then hydrochloric acid, etc., is created. Because it is in a strong acidic and strong acidifying environment, the anode is required to be a highly anti-corrosive electrode. Ferrite, which was selected based on its performance in the past, does not have high electrical conductivity, unlike regular metals, and it is hard and brittle due to it being ceramic. Therefore, it was difficult to connect the terminals using current methods such as welding. In the present invention, a sufficient contact area for the terminals and the ferrite electrodes is prepared so that the conductivity at the contact point is increased.